Glypican-3 induces oncogenicity by preventing IGF-1R degradation, a process that can be blocked by Grb10

Circular SERPINA3 and its target microRNA-944 as potential biomarkers in hepatitis C virus-induced hepatocellular carcinoma in Egyptian population

Background

The most prevalent cancer in Egypt is hepatocellular carcinoma (HCC) mainly due to the infection with the hepatitis C virus. So it is critical to find sensitive biomarkers for early diagnosis of HCC and avoid post-operation tumor recurrence. Therefore, this research was designed to demonstrate the circSERPINA3 role in the regulation of microRNA-944 gene expression in HCV-related HCC cases and compare these results with circSERPINA3 and microRNA-944 gene expression levels in HCV-infected patients.

Methodology

Study participants were divided into three groups: healthy controls, HCV- infected, and HCV-induced HCC patients. The gene expression levels of circSERPINA3 and microRNA-944 were evaluated using Real-Time qPCR. Then the immunoblotting procedure was applied to measure the serum levels of MDM2 and E-cadherin besides, the serum concentration levels of glypican-3 and alpha-fetoprotein were measured by sandwich ELISA.

Results

The gene expression level of circSERPINA3 was significantly upregulated in both HCV-infected and HCC patients causing suppression of the antitumor effect of miR-944 and showing a lower 1-year survival rate than the participants who had low circSERPINA3 gene expression levels. Subsequently, the miR-944 downstream protein, MDM2 was remarkably upregulated, exaggerating the metastasis and oxidative stress in HCC cases. Additionally, the results confirmed the downregulation of microRNA-944 improved the progression of viral hepatitis C cases to hepatocarcinogenesis through the significantly increased serum level of the metastatic marker, E-cadherin. Although alpha-fetoprotein is a common diagnostic marker used in the diagnosis of HCC, our results showed that glypican-3 had greater sensitivity and specificity and positively correlated to the IGF-1 signaling pathway of HCC cases. Moreover, the gene expression levels of circSERPINA3 and E-cadherin in both the HCV and HCV-induced HCC were significantly positively correlated.

Conclusion

circSERPINA3 and miR-944 were sensitive molecular markers for early diagnosis of HCC and could be prospective treatment targets for HCV-infected patients to avoid tumor recurrence in HCC cases.

Extended-Synaptotagmin 1 Enhances Liver Cancer Progression Mediated by the Unconventional Secretion of Cytosolic Proteins

Extended-synaptotagmin 1 (E-Syt1) is an endoplasmic reticulum membrane protein that is involved in cellular lipid transport. Our previous study identified E-Syt1 as a key factor for the unconventional protein secretion of cytoplasmic proteins in liver cancer, such as protein kinase C delta (PKCδ); however, it is unclear whether E-Syt1 is involved in tumorigenesis. Here, we showed that E-Syt1 contributes to the tumorigenic potential of liver cancer cells. E-Syt1 depletion significantly suppressed the proliferation of liver cancer cell lines. Database analysis revealed that E-Syt1 expression is a prognostic factor for hepatocellular carcinoma (HCC). Immunoblot analysis and cell-based extracellular HiBiT assays showed that E-Syt1 was required for the unconventional secretion of PKCδ in liver cancer cells. Furthermore, deficiency of E-Syt1 suppressed the activation of insulin-like growth factor 1 receptor (IGF1R) and extracellular-signal-related kinase 1/2 (Erk1/2), both of which are signaling pathways mediated by extracellular PKCδ. Three-dimensional sphere formation and xenograft model analysis revealed that E-Syt1 knockout significantly decreased tumorigenesis in liver cancer cells. These results provide evidence that E-Syt1 is critical for oncogenesis and is a therapeutic target for liver cancer.

Target Selection for T-Cell Therapy in Epithelial Ovarian Cancer: Systematic Prioritization of Self-Antigens

Adoptive T cell-receptor therapy (ACT) could represent a promising approach in the targeted treatment of epithelial ovarian cancer (EOC). However, the identification of suitable tumor-associated antigens (TAAs) as targets is challenging. We identified and prioritized TAAs for ACT and other immunotherapeutic interventions in EOC. A comprehensive list of pre-described TAAs was created and candidates were prioritized, using predefined weighted criteria. Highly ranked TAAs were immunohistochemically stained in a tissue microarray of 58 EOC samples to identify associations of TAA expression with grade, stage, response to platinum, and prognosis. Preselection based on expression data resulted in 38 TAAs, which were prioritized. Along with already published Cyclin A1, the TAAs KIF20A, CT45, and LY6K emerged as most promising targets, with high expression in EOC samples and several identified peptides in ligandome analysis. Expression of these TAAs showed prognostic relevance independent of molecular subtypes. By using a systematic vetting algorithm, we identified KIF20A, CT45, and LY6K to be promising candidates for immunotherapy in EOC. Results are supported by IHC and HLA-ligandome data. The described method might be helpful for the prioritization of TAAs in other tumor entities.

Effects of targeted-edited oncogenic insulin-like growth factor-1 receptor with specific-sgRNA on biological behaviors of HepG2 cells

BACKGROUND

Insulin-like growth factor-1 receptor (IGF-1R) is over-expressed in hepatocellular carcinoma (HCC). However, the relationship between IGF-1R activation and HCC progression remains unidentified.

AIM

To investigate the effects of editing IGF-1R on the biological features of HCC cells.

METHODS

Immunohistochemistry analyzed the expressions of IGF-1R and P-glyco protein (P-gp) in HCC tissues and their distal non-cancerous tissues (non-Ca). IGF-1R was edited with Crispr/Cas9 system, screened specific sgRNAs, and then transfected into HepG2 cells. CCK-8, scratch wound test detected cell proliferation, migration, invasion and transwell assays, respectively. Alterations of IGF-1R and P-gp were confirmed by Western blotting. Alterations of anti-cancer drug IC₅₀ values were analyzed at the cell level.

RESULTS

The positive rates of IGF-1R (93.6%, χ² = 63.947) or P-gp (88.2%, χ² = 58.448) were significantly higher (P < 0.001) in the HCC group than those (36.6% in IGF-1R or 26.9% in P-gp) in the non-Ca group. They were positively correlated between high IGF-1R and P-gp expression, and they were associated with hepatitis B virus infection and vascular invasion of HCC. Abnormal expressions of circulating IGF-1R and P-gp were confirmed and associated with HCC progression. Biological feature alterations of HCC cells transfected with specific sgRNA showed IGF-1R expression down-regulation, cell proliferation inhibition, cell invasion or migration potential decreasing, and enhancing susceptibility of HepG2 cells to anti-cancer drugs.

CONCLUSION

Edited oncogenic IGF-1R was useful to inhibit biological behaviors of HepG2 cells.

The Role of NEDD4 E3 Ubiquitin–Protein Ligases in Parkinson’s Disease

Parkinson’s disease (PD) is a debilitating neurodegenerative disease that causes a great clinical burden. However, its exact molecular pathologies are not fully understood. Whilst there are a number of avenues for research into slowing, halting, or reversing PD, one central idea is to enhance the clearance of the proposed aetiological protein, oligomeric α-synuclein. Oligomeric α-synuclein is the main constituent protein in Lewy bodies and neurites and is considered neurotoxic. Multiple E3 ubiquitin-protein ligases, including the NEDD4 (neural precursor cell expressed developmentally downregulated protein 4) family, parkin, SIAH (mammalian homologues of Drosophila seven in absentia), CHIP (carboxy-terminus of Hsc70 interacting protein), and SCFFXBL5 SCF ubiquitin ligase assembled by the S-phase kinase-associated protein (SKP1), cullin-1 (Cul1), a zinc-binding RING finger protein, and the F-box domain/Leucine-rich repeat protein 5-containing protein FBXL5), have been shown to be able to ubiquitinate α-synuclein, influencing its subsequent degradation via the proteasome or lysosome. Here, we explore the link between NEDD4 ligases and PD, which is not only via α-synuclein but further strengthened by several additional substrates and interaction partners. Some members of the NEDD4 family of ligases are thought to crosstalk even with PD-related genes and proteins found to be mutated in familial forms of PD. Mutations in NEDD4 family genes have not been observed in PD patients, most likely because of their essential survival function during development. Following further in vivo studies, it has been thought that NEDD4 ligases may be viable therapeutic targets in PD. NEDD4 family members could clear toxic proteins, enhancing cell survival and slowing disease progression, or might diminish beneficial proteins, reducing cell survival and accelerating disease progression. Here, we review studies to date on the expression and function of NEDD4 ubiquitin ligases in the brain and their possible impact on PD pathology.

Multiple subcellular localizations and functions of protein kinase Cδ in liver cancer

Protein kinase Cδ (PKCδ) is a member of the PKC family, and its implications have been reported in various biological and cancerous processes, including cell proliferation, cell death, tumor suppression, and tumor progression. In liver cancer cells, accumulating reports show the bi-functional regulation of PKCδ in cell death and survival. PKCδ function is defined by various factors, such as phosphorylation, catalytic domain cleavage, and subcellular localization. PKCδ has multiple intracellular distribution patterns, ranging from the cytosol to the nucleus. We recently found a unique extracellular localization of PKCδ in liver cancer and its growth factor-like function in liver cancer cells. In this review, we first discuss the structural features of PKCδ and then focus on the functional diversity of PKCδ based on its subcellular localization, such as the nucleus, cell surface, and extracellular space. These findings improve our knowledge of PKCδ involvement in the progression of liver cancer.

Unconventional Secretion of PKCδ Exerts Tumorigenic Function via Stimulation of ERK1/2 Signaling in Liver Cancer

Expression of human protein kinase C delta (PKCδ) protein has been linked to many types of cancers. PKCδ is known to be a multifunctional PKC family member and has been rigorously studied as an intracellular signaling molecule. Here we show that PKCδ is a secretory protein that regulates cell growth of liver cancer. Full-length PKCδ was secreted to the extracellular space in living liver cancer cells under normal cell culture conditions and in xenograft mouse models. Patients with liver cancer showed higher levels of serum PKCδ than patients with chronic hepatitis or liver cirrhosis or healthy individuals. In liver cancer cells, PKCδ secretion was executed in an endoplasmic reticulum (ER)-Golgi-independent manner, and the inactivation status of cytosolic PKCδ was required for its secretion. Furthermore, colocalization studies showed that extracellular PKCδ was anchored on the cell surface of liver cancer cells via association with glypican 3, a liver cancer-related heparan sulfate proteoglycan. Addition of exogenous PKCδ activated IGF-1 receptor (IGF1R) activation and subsequently enhanced activation of ERK1/2, which led to accelerated cell growth in liver cancer cells. Conversely, treatment with anti-PKCδ antibody attenuated activation of both IGF1R and ERK1/2 and reduced cell proliferation and spheroid formation of liver cancer cells and tumor growth in xenograft mouse models. This study demonstrates the presence of PKCδ at the extracellular space and the function of PKCδ as a growth factor and provides a rationale for the extracellular PKCδ-targeting therapy of liver cancer. SIGNIFICANCE: PKCδ secretion from liver cancer cells behaves as a humoral growth factor that contributes to cell growth via activation of proliferative signaling molecules, which may be potential diagnostic or therapeutic targets.

Chromatin accessibility changes are associated with enhanced growth and liver metastasis capacity of acid-adapted colorectal cancer cells

The acidic extracellular microenvironment, namely acidosis, is a biochemical hallmark of solid tumors. However, the tumorigenicity, metastatic potential, gene expression profile and chromatin accessibility of acidosis-adapted colorectal cancer cells remain unknown. The colorectal cancer cell SW620 was cultured in acidic medium (pH 6.5) for more than 3 months to be acidosis-adapted (SW620-AA). In comparison to parental cells, SW620-AA cells exhibit enhanced tumorigenicity and liver metastatic potential in vivo. Following mRNA and lncRNA expression profiling, we validated that OLMF1, NFIB, SMAD9, DGKB are upregulated, while SESN2, MAP1B, UTRN, PCDH19, IL18, LMO2, CNKSR3, GXYLT2 are downregulated in SW620-AA cells. The differentially expressed mRNAs were significantly enriched in DNA remodeling-associated pathways including HDACs deacetylate histones, SIRT1 pathway, DNA methylation, DNA bending complex, and RNA polymerase 1 chain elongation. Finally, chromatin accessibility evaluation by ATAC-sequencing revealed that the differentially opened peaks were enriched in pathways such as small cell lung cancer, pathways in cancer, ErbB signaling, endometrial cancer, and chronic myeloid leukemia, which were mainly distributed in intergenic regions and introns. These results suggest that the chromatin accessibility changes are correlated with enhanced growth and liver metastasis capacity of acid-adapted colorectal cancer cells.

Diagnosis accuracy of serum glypican-3 level in patients with hepatocellular carcinoma: a systematic review with meta-analysis

BACKGROUND

Previous studies have evaluated the diagnostic value of serum glypican-3 in patients with hepatocellular carcinoma. However, the results remain inconsistent and even controversial. Thus, the aim of the present meta-analysis was to clarify the diagnostic accuracy of serum glypican-3 for hepatocellular carcinoma.

METHODS

A meta-analysis including 22 studies was performed with 2325 cases and 2280 controls. Relevant studies were searched in the EMBASE, PubMed, and Web of Science databases, covering relevant papers published until November 1, 2017. The quality of the studies was assessed by revised QUADAS tools. Sensitivity, specificity, and other measures were pooled and determined to evaluate the accuracy of serum glypican-3 in the diagnosis of hepatocellular carcinoma by random-effects models. Summary receiver operating characteristic curve (sROC) analysis was performed to summarize the overall test performance.

RESULTS

The results showed that the pooled overall diagnostic sensitivity, specificity, and 95% confidence interval (CI) for serum glypican-3 in the diagnosis of hepatocellular carcinoma were 68% (56-79%) and 92% (82-96.0%), respectively. Besides, the summary diagnostic odds ratio and 95% CI for glypican-3 were 23.53 (8.57-64.63). In addition, the area under sROC and 95% CI was 0.87 (0.84-0.90). The major design deficiencies of included studies were differential verification bias, and a lack of clear exclusion and inclusion criteria.

CONCLUSIONS

The results of this meta-analysis suggested that serum glypican-3 was acceptable as a moderate diagnostic marker in the diagnosis of hepatocellular carcinoma compared with healthy individuals, which could elevate the sensitivity and specificity of diagnosis. Furthermore, more well-designed studies with large sample sizes are needed to show the effectiveness of glypican-3 in the differential diagnosis of hepatocellular carcinoma.